Pulmonary delivery of therapeutic agents offers several advantages over other modes of delivery. These advantages include rapid onset of action, convenience of patient self-administration, potential for reduced drug side effects, ease of delivery by inhalation, and the elimination of needle. Inhalation therapy is capable of providing a drug delivery system that is easy to use in an inpatient or outpatient setting, results in very rapid onset of drug action, and produces minimal side effects.
MgST is a common excipient used in pharmaceutical formulations. However, MgST is known to catalyze acid-based hydrolysis. Thus, MgST is not compatible with active ingredients susceptible to acid-based hydrolysis, e.g., ASA. Unexpectedly, ASA/MgST formulations disclosed herein showed high ASA stability under various conditions for months. Similar compositions of MgST with other API previously known to be incompatible may also possess unexpected high API stability in the presence of MgST.